The present invention relates to an imaging apparatus and, more particularly, to an imaging apparatus for digitally processing an image signal obtained by an imaging unit.
Recently, reduction in size of digital information units and apparatus has caused a trend for wide-spread use of portable digital information unit/terminals, such as note-type personal computers, PDA (Personal Digital Assistant) personal information terminals, electronic notes, etc. There is also proposed a system, in which an image is picked up with such a portable information unit/terminal, processed and edited or subjected to DTP (desk top publishing) in a visited place for transmitting the image data thus obtained to digital apparatuses or the like in offices though an existing communication network such as telephone lines.
In a usual process of picking up the foreground image into such a portable information unit/terminal, the image signal obtained with a video movie or the like is input as an image signal by using a video input board or the like. According to this process, the image can be acquired comparatively speedily, while it is impossible to obtain image quality higher than that of the video signal. However, the portable information unit/terminal used in visited places usually have no function expansion slot for mounting a function expansion board or the like due to requirements of portability. Therefore, it is difficult to utilize function expansion boards such as video boards.
As other means for realizing the same purpose, a digital still camera has been proposed, which is used with IC cards as recording medium. This digital still camera is capable of easily acquiring the image data at the visited place due to the compact and light weight of the body and the memory medium. With such digital still camera, in order to process or edit the image signal recorded in the IC card, it is necessary to transfer the IC card to the portable information unit/terminal and to read out the data therefrom.
In another process of transmitting the image data, the digital still camera is provided with a data communication interface and connected via cable or the like to the portable information unit/terminal. In this case, however, the data communication speed of the general-purpose interface I/F, such as "RS232C" or "SCSI", which is generally equipped, is slow, and considerable time is required for transmitting one frame of data for the large capacity of the image data.
With the above still camera, at least both the digital still camera and the portable information unit/terminal are necessary in either of the above processes, causing inconvenience of handling in the visited place.
To obviate such inconvenience, an electronic camera having a card-like form like an IC memory card, has been proposed, as disclosed in Japanese Patent Laid-open Publication No. 176168/1989. FIGS. 10 and 11 show the disclosed electronic camera. As shown, the camera has a card-like camera body 51 made of a plastic material. An image pick-up lens 52 is provided substantially at the center of the camera body 51. A CCD image sensor 53 is assembled at a position on the optical axis of and in the focal plane of the image pick-up lens 52. An eyepiece lens 54 is disposed above the image pick-up lens 52 in FIG. 10. A white balance sensor light collection window 55 is provided on the side of the image pick-up lens 52 opposite the eyepiece lens 54. Along the left edge of the camera body 51 in FIG. 10, a plurality of switches 56 including a shutter switch and other mode switches for shutter speed control and date copying are provided such that they are operable from the outside. A connector 57 having a plurality of contacts is provided along the edge opposite the switches 56.
When reproducing the image data recorded by such electronic camera, the circuit thereof is connected to the circuit of a reproducing apparatus (not shown) by inserting the connector 57 thereinto. Such a card-like electronic camera can be used as the recording medium with a portable information unit/terminal. In addition, the data communication speed of the interface provided in the card is so high that the camera is suited for transmitting the video data therefrom to other digital units.
However, the electronic camera proposed in the above Japanese Patent Laid-open Publication No. 176168/1989 pays no attention to a shape thereof for imaging in combination with the portable information unit/terminal. Actually, the disclosed card-like electronic camera has an eyepiece 54 and is adopted for imaging only by itself. When imaging is made with such electronic camera alone, the picked-up picture can not be confirmed on an electronic display or like display means. It is thus difficult to recognize the output image of the picked-up image. Further, according to the sole electronic camera it is impossible to record comments at the time of imaging. Thus, it is necessary to connect the portable information unit/terminal for recording the desired data or comments.
Further, according to the publication as noted above, the eyepiece lens 54 and image pick-up lens 52 are mounted such that their optical axes extend in the thickness direction of the camera body. Therefore, the camera body is required to have a considerable thickness. Actually, it is difficult to provide an electronic camera having approximately the same thickness as that of an IC memory card. Moreover, the eyepiece lens has to occupy a certain area, thus inevitably leading to a size increase of the card part of the camera.